Thermotemporal responsive device



Oct-19, 1948. w SAMBUR THERMOTEMPORAL RESPONSIVE DEVICE INVENTOR.

2 Sheets-Sheet 2 Filed Nov. 13, 1942 l atented Oct. 19, 194

UNITED STATES PATENT OFFICE THERMOTEMPORAL RESPONSIVE DEVICE "WilliamSambur, Jamaica, N. Y.

'Application'November 13, 1942, Serial No. 465,43?

an improved control device of the character described which shall besimple in design, relatively inexpensive to manufacture and install,-easy to assemble, rugged in construction, neatin appear ance, and whichat thesame time shall operate with a high degree of usefulnessandefficiency.

ther objectsof the invention will in part be obvious and in parthereinafter pointed out.

The invention accordingly consists of-thereatures of construction,combinations ofoelements, and arrangement of parts which will beexemplified in the construction hereinafter describedand of which thescope of' application will be indicated in the appended claims.

'In the accompanying drawings, in which is shown one of the variouspossibleembodiments of the-invention,

Fig. 1 is a schematic circuit diagram of. the improved control device;

Fig. 2 is a perspective view'of-the trolbox;

Fig. 3 is a detail view of one of the variably positioned temporallyresponsive control elements mounted in the control box;

Fig. 4 is adetailface-view which-is illustrative of the cooperationbetween such element and a clock-controlled contact arm;

Fig. 5 is a sectional viewthrough said element and arm and further showsin dotted lines the position the arm assumes when it is-out ofcontactwith theelement; and

Fig. 6 is a front view of a control switch-used indoorconin the controldevice.

selected periods to be easily and readily .varied Y to accommodatefor-long range changesin the quantity of demandpto automatically shutoff the mechanism when the ambient temperature .-ex-

ceeds the preselected higher temperature; to

automatically continuously operate the mechanism when the ambienttemperature falls below the lower of the two preselected ambienttemperatures; to enable the'preselected temperatures to be easily andreadily varied-toaccommodate for long range changes in the quality ofdemand; and'to lengthen the periodic operations of the, device inproportion to the fall of ambient temperature when the ambienttemperature fluctuates between the higher and lower preselectedtemperatures.

- Heretofore, these several functions werecar- 'ried out by controldevices comprisinga-combination of a large number of means of whichcertain, such as the high temperature shut off, were independentlyoperating mechanisms, 7 and of which practicall all were-complicatedmechanicalsstructures requiring many accurately machined parts. As aresult previous controls of the character described were large and bulkymechanisms which were difiicult and expensive to manufacture, installand repair and often broke down during use.

In accordance with the present invention there is provided a controldevice of the character described which avoids the foregoingdifiiculties and drawbacks by employing a thermally responsiveelectrical means-and aplurality of temporally responsive electricmeansall of which mutually coact in combination with other electrical meansto obtain the desired functions. Thethermally and temporallyresponsivemeans may be mechanically operated b simple, ruggedmechanismsbut, preferably,-only the temporally responsive means is so-actuated andthe thermally responsive means instead employs a well-known,non-mechanical, thermoelectric phenomenon.

More specifically the improved control device comprises an .outdoorelement which includes an electrical means whoseimpedance varies.toconform tochangesin ambient temperature. Such means can comprisetin-inductance, a capacitance, or a resistance where alternating currentis-used as a source of power. For reasons which will shortly beapparent,-the preferred form of the invention, hereinafter described indetail, employs a resistance. The impedance value of. the electricalmeans can be varied by any simple, ruggedmechanism, such-as a bellows orbimetallic element-but as previously noted, it is desirable although theinvention is not so limited, to.employ a well-known thermoelectricphenomenon,

.:to wit: the variation in resistance'of a resistor with change oftemperature.

The control device also comprises an indoor control .box whichessentially includes a plurality of electric means whose impedancevaries with the passage of time. Such means can, like the outdoorelement comprise an inductance, a capacitance or a resistance, althoughthe invention is most easily carried out by use of a resistance. Theimpedance value of the electrical means is preferably varied by aclock-controlled mechanism, it being understood however, that other timemeasuring means are within the scope of the invention.

The indoor control box further includes a switch which closes uponapplication of a certain potential. Examples of such switches are theglow heated bimetallic switch and electronic tube. When switches such asthese are employed it is additionally necessary to use an independenthigh ambient temperature cut-oft or low ambient temperature lock-inmeans. There is, therefore, preferably employed a switch which inaddition to the foregoing characteristic opens when, after closing, theapplied potential drops below a certain potential, lower than thepotential' required to close the switch. Switches of theelectro-magnetic type have both these characteristics.

The switch, thermally responsive electrical means, and temporallyresponsive electrical means are electrically connected in a circuit suchthat the period of operation of the mechanism being controlled,following a minimum period of operation, is a function of the ambienttemperature. To this end the thermally responsive and temporallyresponsive electrical means may be connected in a series, parallel, orseries-parallel circuit depending upon whether in these variouselectrical means the impedance increases or lowers with a rise intemperature and the passage of time.

Finally the indoor control box includes sundry means for rendering theoperation of the control device highly flexible, for increasing safety,and for simplifying installation.

Referring now in detail to the drawings, there is disclosed an outdoorelement I6 (Fig. 1) comprising a weatherproof, watertight housing l2 ofan electrically non-conductive material such as Bakelite or mica, onwhich is supported in conventional manner, as by winding or traversing,a coiled resistor l6 of a material whose resistance varies with itstemperature. A typical material which is satisfactory for this purposeis an ironnickel alloy consisting of 70% nickel and 30% iron. This allohas about twice the resistance of commercially pure nickel and the slopeof its temperature-resistance curve is straight from C. to over 100 C.Saidalloy is known as Balco. The two ends of the resistor 16 lead toterminals I8, 26 which are detachably received in a conventional socket(not shown). In order to facilitate description the resistance value forsuch resistor will now be assigned, it being understood however, thatsuch value, as well as all other values hereinafter assigned to thevarious elements of the control device, are given by way of exampleonly, and are in no way to be construed as a limitation upon theinvention. The resistance value of the resistor I6 is 175 ohms at atemperature of 60 F. and 153 ohms at 20 F. The resistance value betweensaid temperatures is a linear function of the temperature.

The indoor control box 22 (Fig. 2) comprises a metallic box 24 closed bya hinged cover 26. A panel 28 is firmly secured to the box 24 by screws30 and angle irons (not shown). Said panel is fabricated from anelectrically non-conductive with the clock shaft 34.

material of appreciable strength, such as Bakelite or Fibreboard andsupports all indoor operative elements of the control device. The panelcarries on its rear face a synchronous twentyfour hour electric clock 32(Fig. 1) whose shaft 34 (Fig. 5) projects through an aperture 36 in saidpanel. A knob 33 facilitates setting of the shaft. The clock terminals40, 42 are electrically connected to line terminals 44, 46 for analternating current source by lead wires 48, 56, 52, 54 through asingle-throw double-pole manually operated switch 56 accessibly mountedon the panel 28. Line terminals 44, 46 are also connected by lead wires56, 54 to the primary 58 of a step down transformer 60. The oppositeends of the transformer secondar 62 are connected to a full waverectifier 64 by lead wires 65, 68. The output potential of saidrectifier is 9.5 volts. The center tap ill of the transformer isconnected by a lead wire 12 to an iron-core solenoid 14 mounted on therear of the panel 28. Said solenoid acts as the electro-magneticactuating element of a control switch generally indicated by the numeral16. This switch also includes a glass envelope 78 rigidly secured to thepanel. An arm 86 is pivotally mounted in said envelope on a spiralspring 82 which biases the arm away from the solenoid 14 disposedadjacent the glass envelope i8. An iron bar carried on the arm increasesits attraction for the solenoid when the same is sufficiently energized.The lower end of the envelope contains a pool 84 of mercury which withthe free end of the arm 80 forms the two operating contacts of theswitch 16. When the solenoid is fully energized the free end of the armis in the pool 84 and when the solenoid is de-energized the free end ofthe arm is spaced from said pool.

The switch parts are so proportioned and arranged that when a totalimpedance of ohms is interposed between the rectifier 64 and thesolenoid T4 the switch will close and that when this impedance isincreased to 230 ohms, the switch will open. By virtue of thedifferential, the total impedance must drop to 180 ohms to close theswitch and be raised to 230 ohms to open the switch.

Suitable means is provided to vary the impedance interposed between therectifier 6d and switch 16 in accordance with a predetermined minimumcontrol schedule, and the ambient temperature and passage of timebetween the minimum operation periods of such schedule. Such meanscomprises a contact arm 86 which rotates Said arm is electricallyconnected by a lead wire 88 to the rectifier 64. The arm is of aresilient electrically conductive material such as phosphor bronze andis adapted to have a portion thereof adjacent the free end ride on thesurface of an electrically conductive ring :50 imbedded in the panel 28.To simplify the wiring diagram, the bottom portion of the ring is brokenaway in Fig. 1. Said ring is disposed concentrically of the clock shaft34 and projects from the front face of the panel. The ring is connectedby lead wire 92 to a compensating resistance 94 of 10 ohms. The contactarm 96 associated with this resistance is manually rotated by a handle98 having an index pointer which cooperates with temperature indicatingmarkings lllil on the control panel. As will soon be seen, the positionof the handle 98 regulates the indoor temperature of a building heatedby a burner which is controlled by the device being described.

The resistor arm 95. is connected by leadwire IOZto a Contact 55 3 forthe outdoor eler'n'e'nt'lfl. This'contact we and the other outdoorelement contact] 96 arecon'nected to said outdoor element by a panel"thermostat wires I98, 'I I0. Because the potential applied to thesewires can never be re'atrthan the rectified. potential or volts",theiri'stallatioribf such wires is an extremely simple affair and theirshort c'ircuiting cannot createa fire hazard. The second element 'terminal M16. is connected to the solenoid'by lead wire H2 completing'theenergizing circuit.

The switch contact Bil is connected to the burner terminal I i l by leadwire H6. 'The other switch'co'ntac't 85 is connectedtoburnerterminal ilflbyle'ad wire i 25, contact pointji22 of athree way switch i2 3, contact'arm 1250f "said switch lead' wirfe I28 and finally twoepoleswltchfit." Of,

I32 and close-the circuit between the burner ter'- minalsj'and when thehandle pointer is regis-' tere d' with the Automatic indicia. thecircuit connecting the burner terminals will include the switch contacts86, 84.

There are alsoprovided a plurality of temporally responsive controlelements I38 comprising a thin flexible strip I 38 of an electricallynon conductive material such as Bakelite. Wound upon this strip are twoseries-connected resistors I48, M2. The resistor Mfi'has a value of'50ohms and consists of high'resistance wire closely wound so 'as to occupya relatively small space "for rea-' sons-which will soon be apparent.The resistor M2 on the other hand is of a lower resistance wire and hasits turns more WidBly' spaced. 'The end'of said resistor M2 spaced fromthe resistor Mil is anchored to the strip 58 by an eyelet 144. The" endof the resistor Mi? spaced from resistor M2 is caught under a slopingelectrically con ductive clip l lfi held to the strip Hi8 by an eyeletM8 having an integral electrically conductive tail 150., The elementsE36 are removably, snugly and firmly received in a circular groove I52having the same center as the ring 98 but of larger diameter. Said.elements are so fashioned that when positioned inihe groove #52 theywill ex tend further from the panel 28, than said ring. The sloping clipis designed so that its higher end is level with the top edge of thewound resistors Mil, I42 andits lower edge approximately level with asilver contact 154 at the end of the clock contact armed-when said armis riding on the' ring 95. the ring 99.

There is also inserted in the groove I51 anight The tail 550 is curvedtorcontact strip I55 comprising a strip of Bakelite? for the majorportion of its length. On the end of the night strip, near morningoperation of theburner,

a long 22 ohm resistance 55 8 is provided similar to the resistance M2.Thisresistanoehasacon; tact tail 55 similar to the elements 13,6.

The several elementslat and night strip J55 e arran e? in the sw re. 5.?9. e. eave the tails I 56 employed on 6.. space therebetween which, aswill soon be. apparent, govern the minimum schedule'of opera; tionsofthe mechanismvgoverne'd by the control y The operation otthe deviceWlllbg CQIlSideIielcompensating resistance which: for ordinary operationis set midway will have a. resistance of 5 ohms' 'Tliusl'whe n thecontactarm 8 6 i s riding on the'fin lgg; 179.5. chin will beinterposedin series between the rectifier 64 an d the solenoid 14.v 'Under tlfiese"ci cumstances the switch Hi-will be closed. After the arm reachestheendof he sh rt. r quicklybe added tototal 229.5 oh' ns'so that whenthe arm reaches theendiof; said resistorv I40 the switch 'lfi will stille, closed; marks the. end of a predetermined minimum operating period.As the; arm 86,.trave ls'iurther it will soon cut in 0,5 ohm of thelong22' ohm resistorl l? so that shortly after the arm has commenced to rideon said resistor I42 a total of 230-ohms will be in er i ih en l ndcauseh Switch contacts 80, 8 l .t o separate shutting oil; the oil. burner.

At 4 0? F.- the outdoor element will have a resistance ofabout 1:6 4ohms so that the switch '16; wlllremain closed. until the'contact arm 86has ail r nou h alone e es tor 1. .2 t t in 11 ohms and open thecontacts 80, 84. It will thus be seen that the length of the resistanceI42 governs thelength of operation added to the min imum period ofoperation. The elements I36 may be set in accordance with theknowndemand for the mechanism (oil burner) regulated by the control device;

At 20 F. the outside element has a resistance value of .153 ohmssothatwhen the contact arm 86.reaches the end of the resistance I42 230ohms will be cut in to open the switch 76. However as soon as thishappens the arm 86;.wi11 drop back raised, It will also decrease andraise, respectively, the mean temperature .of. a, building heatedwithanoilburner governedby the control device.

The actionofthe night strip 156 is as follows:

Whenthe contact armflfirideson thebare portionof the strip 15 6 it willbe raised ofi' the ring 90 and openthe energizingcircuit for thesolenoid. 16 so that for a givenperiod of time, for example irom 1 a, m.to 5;a. m. (Fig. 2) the oil burner will beshut cit-regardless of ambienttemp a u e i The foregoing is true if no resistance winding I58 isemployed. If such winding is used, then,

when the arn B G rides thereon, a resistance equal ling the sum, of theoutdoor resistance Hi, the

compensating resistance 94, and the resistance ohm'resistor I40resistance will 158 is again placed in circuit, It should be noted thatmovement of the arm 86 along the resistance I58 decreases the resistancein circuit as contrasted to movement of the arm 85 along one of theresistances I42 which increases the resistance in circuit.

To explain the operation of the resistance i58 an ambient temperature of40 F. will be considered. At this temperature the outside element 50 hasa resistance value of 164 ohms, the compensating resistance a value ofohms, and when the arm 86 first rides on the resistance 158, saidresistance has a value of 22 ohms. Thus when said arm 86 first touchesthe resistance I58 a total of i9! is in circuit and the switch 16 willremain open. When the arm 86 reaches the middle of the resistance Q58the total resistance will have decreased to 180 ohms, enough to closethe switch 16 and start the oil burner. At higher temperatures theburner will start later, and at lower temperatures earlier.

If any surge potential is noted which tends to start operation when thearm 86 first contacts the resistance I58, an additional short highresistance (not shown) similar to the resistance M0 can be placed at theend of the resistor I58 remote from the tail I 50.

It will be understood, of course, that as long as the switch 50 is open,the control device will not function.

It may be mentioned that variation in the rectified potential arisingfrom aging of the rectifier 64 over long periods of time (12,000 hours)can be corrected by adjusting the compensating resistance 94.

It will thus be seen that there is provided a device which achieves theseveral objects of this invention and which is Well adapted to meet theconditions of practical use.

As various possible embodiments might be made of the above invention andas various changes might be made in the embodiments above set forth, itis to be understood that all matters herein set forth or shown in theaccompanying drawings is to be interpreted as illustrative and not in alimiting sense.

Having thus described my invention, I claim as new and desire to secureby Letters Patent:

1. A control device for intermittently operating a mechanism withrespect to a predetermined outdoor temperature range for periods of timewhich increase in proportion to decreases of temperature within saidrange, said device comprising a control switch for turning saidmechanism off and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating meansbeing governed by the value of the potential applied thereto, saidcircuit including time controlled means to render said actuating meansoperative .to set said mechanism in operation at a preselected time ofthe day, means to vary the potential applied to said actuating means inproportion to temperature, and time controlled means to vary thepotential applied to said actuating means in proportion to the timeelapsed after a preselected period of time following the beginning of aperiod of .operation of the mechanism at said preselected time so as tostop operation of said mechanism after a time lapse following thepreselected period of time, said lapse being proportional totemperature.

2. A control device for intermittently operating a mechanism withrespect to a predetermined outdoor temperature range for periods of time8 which increase in proportion to decreases of temperature within saidrange, said device comprising a control switch for turning saidmechanism oil and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating meansbeing governed by the value of the potential applied thereto, saidcircuit including time controlled means to render said actuating meansoperative to set said mechanism in operation at a preselected time ofthe day, means to vary the potential applied to said actuating means inproportion to temperature, and time controlled means to vary thepotential applied .to said actuating means in proportion to the timeelapsed after a preselected period of time following the beginning of aperiod of operation of the mechanism at said preselected time so as tostop operation of said mechanism after a time lapse following thepreselected period of time, said lapse being proportional totemperature, said last named means varying the potential in a directionopposite to that in which it is varied by a decrease in temperature.

3. A control device for intermittently operating a mechanism withrespect to a predetermined outdoor temperature range for periods of timewhich increase in proportion to decreases of temperature within saidrange, said device comprising a control switch for turning saidmechanism off and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating meansbeing governed by the value of the potential applied thereto, saidcircuit including time controlled means to render said actuating meansoperative to set said mech anism in operation at a preselected time ofthe day, means .to vary the potential applied to said actuating means inproportion to temperature, and time controlled means to vary thepotential applied to said actuating means in proportion to the timeelapsed after a preselected period of time following the beginning of aperiod of operation of the mechanism at said preselected time, said lastnamed means varying the potential in a direction opposite to that inwhich it is varied by a decrease in temperature so as to stop operationof said mechanism after a time lapse following the preselected period oftime, which lapse is inversely proportional to temperature.

4. A control device for intermittently operating a mechanism withrespect to a predetermined out-door temperature range for periods oftime which increase in proportion to decreases of temperature withinsaid range, said device comprising a control switch for turning saidmechanism ofi and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating meansbeing governed by the value of the potential applied thereto, saidcircuit including a plurality of time controlled means to render saidactuating means operative to set said mechanism in operation atdifferent preselected times of the day, means to vary the potentialapplied to said actuating means in proportion to temperature, and aplurality of time controlled means to vary the potential applied to saidactuating means in proportion to the time elapsed after preselectedperiods of time following the beginnings of period-s of operation of themechanism at said preselected times so as to stop operations of saidmechanisms after time lapses following the preselected period of time,which lapses are inversely proportional to temperature, said last namedmeans varying the potential in 9 a direction opposite to that in whichit is varied by a decrease in temperature.

5. A control device for intermittently operating a mechanism withrespect to a predetermined outdoor temperature range for periods of timewhich increase in proportion to decreases of temperature within saidrange, said device comprising a control switch for turning saidmechanism oil and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating mean-sbeing governed by the value of the potential applied thereto, saidcircuit including time controlled means to ren der said actuating meansoperative to set said mechanism in operation at a preselected time ofthe day, means to vary the potential applied to said actuating means inproportion to temperature, and time controlled means to vary thepotential applied to said actuating means in proportion .to the timeelapsed after a preselected period of time following the beginning of aperiod of operation of the mechanism at said preselected time so as .tostop operation of said mechanism after a time lapse following thepreselected period of time, which lapse is proportional to temperature,said last named means varying the potential in a direction opposite tothat in which it is varied by a decrease in temperature, the overallchange in potential effected by the potential varying temperatureresponsive means over its full range of operation being of the sameorder as the over-all change in potential effected by the potentialvarying time controlled means over the latters full range of operation.

6. A control device for intermittently operating a mechanism withrespect to a predetermined outdoor temperature range for periods of timewhich increase in proportion to decreases of temperature within saidrange, said device comprising a control switch for turning saidmechanism off and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating meansbeing governed by the value of the potential applied thereto, saidcircuit including time controlled means to render said actuating meansoperative to set said mechanism in operation at a preselected time ofthe day, means to vary the potential applied to said actuating means inproportion to temperature and in such direction upon a decrease intemperature as to inhibit an actuation of the switch which would stopthe mechanism from operating, and time controlled means to vary thepotential applied to said actuating means in proportion to the'timeelapsed after a preselected period of time following the beginning of aperiod of operation of the mechanism at said preselected time and in adirection opposite to that in which it is varied by a decrease intemperature so as to stop operation of said mechanism after a time lapsefollowing the preselected period of time, which lapse is inverselyproportional to temperature, whereby a change in the potential appliedto said actuating means, which change is efiected by the potentialvarying temperature responsive means and results from a decrease intemperature, is counteracted with the passage of time following saidpreselected period of time by the change in potential which is effectedby the potential varying time controlled means, and the period ofopcontrolled means are variable impe-dances.

8. A control device as set forth in claim 6 wherein the potentialvarying temperature responsive means and the potential varying timecontrolled means are variable resistances.

9. A control device as set forth in claim 6 wherein the potentialgoverning the operation of the actuating means is such that the changein potential effected by the potential varying temperature responsivemeans at temperatures above the predetermined temperature range rendersthe first named time controlled means ineffective to set the mechanismin operation at a preselected time of the day.

10. A control device as set forth in claim 6 wherein the potentialgoverning the operation of the actuating means is such that the changein potential effected by the potential varying temperature responsivemeans at temperatures below the predetermined temperature range rendersthe potential varying time controlled means ineffective to stopoperation Of the mechanism.

11. A control device for intermittently operating a mechanism withrespect to a predetermined outdoor temperature range for periods of timewhich increase in proportion to decreases of temperature within saidrange, said device comprising a control switch for turning saidmechanism off and on and an energizing circuit including an electricactuating means for said switch, the operation of said actuating meansbeing governed by the value of the potential applied thereto, saidcircuit including time con trolled means to render said actuating meansoperative to set said mechanism in operation at a preselected time ofthe day, and time controlled means for varying the potential applied tosaid actuating means in such manner as to cause interruption of theoperation of said mechanism after an interval, determined bytemperature, starting after a preselected period of time following thebeginning of a period of operation of the mechanism at said preselectedtime.

WILLIAM SAMBUR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Great Britain Apr. 20, 1936

